Calculating Expected Value

12th GradeMath60 min

Learning Objective

I can calculate the expected value of a random variable.

Lesson Flow

Watch Video

5 min

Mean (expected value) of a discrete random variable | AP Statistics | Khan Academy

Khan Academy

Guided Notes

12 min

Key concepts students will learn:

  • A discrete random variable has a finite number of values, and a valid probability distribution has a combined probability of one.

  • The expected value of a discrete random variable is the weighted sum of the various outcomes, weighted by their probabilities.

  • The expected value, or mean, of a random variable can be a non-integer value even if the random variable only takes on integer values.

Practice

18 min

12 questions • Multiple choice & Short answer & True/false

Exit Ticket

5 min

A discrete random variable Y represents the number of days per week a person exercises. The probability distribution is as follows: P(Y=0) = 0.2, P(Y=1) = 0.1, P(Y=2) = 0.3, P(Y=3) = 0.4. What is the expected value of Y? Show your work.

Teacher Guide

Get the complete package:

  • Answer keys for all questions
  • Differentiation strategies
  • Extension activities
  • Printable student handouts

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